Whatever the precise magnitude of the CRA’s role, there is no question that as the government pursued affordable-housing goals—with the CRA providing approximately half of Fannie’s and Freddie’s affordable-housing purchases—trillions of dollars in high-risk lending flooded the real-estate market, with disastrous consequences. Over the last 20 years, the percentage of conventional home-purchase mortgages made with the borrower putting 5 percent or less down more than tripled, from 8 percent in 1990 to 29 percent in 2007. Adding to the default risk: of these loans with 5 percent or less down, the average down payment declined from 5 percent to 3 percent of the loan’s value.

As for Fannie and Freddie, most of the loans with 5 percent or less down that they had acquired by 2005 had down payments of 3 percent or even no down payment at all. From 1992 to 2007, the two entities acquired over $3.1 trillion in low-down-payment or credit-impaired loans and private securities backed by credit-impaired loans—and these are performing horribly: the delinquency rate on Fannie’s and Freddie’s remaining $1.1 trillion in such high-risk loans is 15.5 percent as of this past June 30, about 6.5 times the rate on the entities’ traditionally underwritten loans. All this risky lending, of course, drove the nation’s homeownership rate up and inflated a housing-price bubble.